The 2015 population of the region is higher by 222,430 compared with the population of 3.41 million in 2010, and by 798,371 compared with the population of 2.83 million in 2000. Refer to Table 1.

The population of Region IX increased by 1.21 percent annually, on average, during the period 2010 to 2015. By comparison, the rate at which the region’s population grew during the period 2000 to 2010 was higher at 1.87 percent. See Table 2.

Among the three provinces comprising the region, Zamboanga del Norte had the biggest population in 2015 with 1,011,393 persons, followed closely by Zamboanga del Sur with 1,010,674 persons. Zamboanga Sibugay had the smallest population with 633 thousand. Refer to Table 3.

Zamboanga City, the only highly urbanized city in the region posted a population of 862 thousand.

The City of Isabela, on the other hand had a population of 113 thousand. This city is a component city in Region IX whose province, Basilan, is under the regional jurisdiction of the Autonomous Region in Muslim Mindanao (ARMM).

The total population of Region IX accounted for about 3.6 percent of the Philippine population in 2015.

Zamboanga Sibugay was the fastest growing province in the region with an average annual population growth rate (PGR) of 1.53 percent during the period 2010 to 2015. It was followed by Zamboanga del Norte (1.04 percent) and Zamboanga del Sur with 0.99 percent. See Table 4.

Region IX is composed of one highly urbanized city, four component cities (including the City of Isabela), 67 municipalities, and 1,904 barangays.

Among the cities and municipalities in the region, the largest in terms of population size is Pagadian City, Zamboanga del Sur with 199,060 persons. It was followed by Dipolog City, Zamboanga del Norte (130,759) and the City of Isabela, Basilan (112,788). Refer to Table 5.

La Libertad in Zamboanga del Norte is the least populous city/municipality in Region IX with 8,406 persons. It was followed by Josefina in Zamboanga del Sur (11,799) and Mutia in Zamboanga del Norte (12,675). See Table 6.

Of the 1,904 barangays in Region IX, the top ten largest in terms of population size are all located in Zamboanga City. Topping the list of the most populous barangays in the region is Talon-talon with 34,916 persons, followed by Mampang (34,312) and Tumaga (30,824). Refer to Table 7.